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Summarizing multiple columns with dplyr? [duplicate]
...1
#> 2 2 3.03 3.04 2.97 2.87
#> 3 3 2.85 2.95 2.95 3.06
If you want to summarize only certain columns, use summarise_at or summarise_if functions.
Alternatively, the purrrlyr package provides the same functionality:
library(purrrlyr)
df %>% slice_rows("grp") %>% dmap(mea...
What is path of JDK on Mac ? [duplicate]
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– Someone Somewhere
Dec 18 '14 at 23:06
44
found it here: /Library/Java/JavaVirtualMachines/jdk1.8...
How do I get extra data from intent on Android?
... method ??
– Adham
Nov 20 '10 at 17:06
49
@adham: If you are in an activity, from within onCreate...
How to calculate time in hours between two dates in iOS
...te];
NSDate *d2 = [NSDate dateWithTimeIntervalSince1970:1340323201];//2012-06-22
NSDateComponents *components = [c components:NSHourCalendarUnit fromDate:d2 toDate:d1 options:0];
NSInteger diff = components.minute;
NSDayCalendarUnit|NSHourCalendarUnit|NSMinuteCalendarUnit
Change needed components...
Showing Difference between two datetime values in hours
...ason for it?
– Neha
May 6 '15 at 11:06
8
Nullable would need a .Value.TotalHours instead of just ...
Missing styles. Is the correct theme chosen for this layout?
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edited Dec 18 '15 at 8:06
answered Aug 21 '14 at 8:22
gb...
Most tricky/useful commands for gdb debugger [closed]
...e).
– Sam Whitlock
Oct 16 '17 at 13:06
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Asp.net - Add blank item at top of dropdownlist
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edited Nov 5 '08 at 23:06
answered Nov 5 '08 at 23:01
St...
How can I check if a checkbox is checked?
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answered Jun 8 '12 at 10:06
shenbaga kannanshenbaga kannan
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How do I call one constructor from another in Java?
...ructor.
– Jon Skeet
Nov 2 '12 at 18:06
44
This has to appear on the first line, but you can do ca...